The patch titled
Subject: mmap: convert __vma_adjust() to use vma iterator
has been added to the -mm mm-unstable branch. Its filename is
mmap-convert-__vma_adjust-to-use-vma-iterator.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mmap-convert-__vma_adjust-to-use-vma-iterator.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>
Subject: mmap: convert __vma_adjust() to use vma iterator
Date: Thu, 5 Jan 2023 19:16:00 +0000
Use the vma iterator internally for __vma_adjust(). Avoid using the
maple tree interface directly for type safety.
Link: https://lkml.kernel.org/r/20230105191517.3099082-28-Liam.Howlett@xxxxxxxxxx
Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/mm.h | 3 -
mm/mmap.c | 75 +++++++------------------------------------
2 files changed, 13 insertions(+), 65 deletions(-)
--- a/include/linux/mm.h~mmap-convert-__vma_adjust-to-use-vma-iterator
+++ a/include/linux/mm.h
@@ -2832,9 +2832,6 @@ extern struct vm_area_struct *copy_vma(s
bool *need_rmap_locks);
extern void exit_mmap(struct mm_struct *);
-void vma_mas_store(struct vm_area_struct *vma, struct ma_state *mas);
-void vma_mas_remove(struct vm_area_struct *vma, struct ma_state *mas);
-
static inline int check_data_rlimit(unsigned long rlim,
unsigned long new,
unsigned long start,
--- a/mm/mmap.c~mmap-convert-__vma_adjust-to-use-vma-iterator
+++ a/mm/mmap.c
@@ -494,56 +494,6 @@ static void __vma_link_file(struct vm_ar
flush_dcache_mmap_unlock(mapping);
}
-/*
- * vma_mas_store() - Store a VMA in the maple tree.
- * @vma: The vm_area_struct
- * @mas: The maple state
- *
- * Efficient way to store a VMA in the maple tree when the @mas has already
- * walked to the correct location.
- *
- * Note: the end address is inclusive in the maple tree.
- */
-void vma_mas_store(struct vm_area_struct *vma, struct ma_state *mas)
-{
- trace_vma_store(mas->tree, vma);
- mas_set_range(mas, vma->vm_start, vma->vm_end - 1);
- mas_store_prealloc(mas, vma);
-}
-
-/*
- * vma_mas_remove() - Remove a VMA from the maple tree.
- * @vma: The vm_area_struct
- * @mas: The maple state
- *
- * Efficient way to remove a VMA from the maple tree when the @mas has already
- * been established and points to the correct location.
- * Note: the end address is inclusive in the maple tree.
- */
-void vma_mas_remove(struct vm_area_struct *vma, struct ma_state *mas)
-{
- trace_vma_mas_szero(mas->tree, vma->vm_start, vma->vm_end - 1);
- mas->index = vma->vm_start;
- mas->last = vma->vm_end - 1;
- mas_store_prealloc(mas, NULL);
-}
-
-/*
- * vma_mas_szero() - Set a given range to zero. Used when modifying a
- * vm_area_struct start or end.
- *
- * @mas: The maple tree ma_state
- * @start: The start address to zero
- * @end: The end address to zero.
- */
-static inline void vma_mas_szero(struct ma_state *mas, unsigned long start,
- unsigned long end)
-{
- trace_vma_mas_szero(mas->tree, start, end - 1);
- mas_set_range(mas, start, end - 1);
- mas_store_prealloc(mas, NULL);
-}
-
static int vma_link(struct mm_struct *mm, struct vm_area_struct *vma)
{
VMA_ITERATOR(vmi, mm, 0);
@@ -703,7 +653,7 @@ int __vma_adjust(struct vm_area_struct *
bool vma_changed = false;
long adjust_next = 0;
int remove_next = 0;
- MA_STATE(mas, &mm->mm_mt, 0, 0);
+ VMA_ITERATOR(vmi, mm, 0);
struct vm_area_struct *exporter = NULL, *importer = NULL;
if (next && !insert) {
@@ -788,7 +738,7 @@ int __vma_adjust(struct vm_area_struct *
}
}
- if (mas_preallocate(&mas, vma, GFP_KERNEL))
+ if (vma_iter_prealloc(&vmi, vma))
return -ENOMEM;
vma_adjust_trans_huge(orig_vma, start, end, adjust_next);
@@ -834,7 +784,7 @@ int __vma_adjust(struct vm_area_struct *
if (start != vma->vm_start) {
if ((vma->vm_start < start) &&
(!insert || (insert->vm_end != start))) {
- vma_mas_szero(&mas, vma->vm_start, start);
+ vma_iter_clear(&vmi, vma->vm_start, start);
VM_WARN_ON(insert && insert->vm_start > vma->vm_start);
} else {
vma_changed = true;
@@ -844,8 +794,8 @@ int __vma_adjust(struct vm_area_struct *
if (end != vma->vm_end) {
if (vma->vm_end > end) {
if (!insert || (insert->vm_start != end)) {
- vma_mas_szero(&mas, end, vma->vm_end);
- mas_reset(&mas);
+ vma_iter_clear(&vmi, end, vma->vm_end);
+ vma_iter_set(&vmi, vma->vm_end);
VM_WARN_ON(insert &&
insert->vm_end < vma->vm_end);
}
@@ -856,13 +806,13 @@ int __vma_adjust(struct vm_area_struct *
}
if (vma_changed)
- vma_mas_store(vma, &mas);
+ vma_iter_store(&vmi, vma);
vma->vm_pgoff = pgoff;
if (adjust_next) {
next->vm_start += adjust_next;
next->vm_pgoff += adjust_next >> PAGE_SHIFT;
- vma_mas_store(next, &mas);
+ vma_iter_store(&vmi, next);
}
if (file) {
@@ -882,8 +832,7 @@ int __vma_adjust(struct vm_area_struct *
* us to insert it before dropping the locks
* (it may either follow vma or precede it).
*/
- mas_reset(&mas);
- vma_mas_store(insert, &mas);
+ vma_iter_store(&vmi, insert);
mm->map_count++;
}
@@ -929,7 +878,7 @@ again:
if (insert && file)
uprobe_mmap(insert);
- mas_destroy(&mas);
+ vma_iter_free(&vmi);
validate_mm(mm);
return 0;
@@ -2061,7 +2010,8 @@ int expand_upwards(struct vm_area_struct
anon_vma_interval_tree_pre_update_vma(vma);
vma->vm_end = address;
/* Overwrite old entry in mtree. */
- vma_mas_store(vma, &mas);
+ mas_set_range(&mas, vma->vm_start, address - 1);
+ mas_store_prealloc(&mas, vma);
anon_vma_interval_tree_post_update_vma(vma);
spin_unlock(&mm->page_table_lock);
@@ -2143,7 +2093,8 @@ int expand_downwards(struct vm_area_stru
vma->vm_start = address;
vma->vm_pgoff -= grow;
/* Overwrite old entry in mtree. */
- vma_mas_store(vma, &mas);
+ mas_set_range(&mas, address, vma->vm_end - 1);
+ mas_store_prealloc(&mas, vma);
anon_vma_interval_tree_post_update_vma(vma);
spin_unlock(&mm->page_table_lock);
_
Patches currently in -mm which might be from Liam.Howlett@xxxxxxxxxx are
maple_tree-add-mas_init-function.patch
maple_tree-fix-potential-rcu-issue.patch
maple_tree-reduce-user-error-potential.patch
test_maple_tree-test-modifications-while-iterating.patch
mm-expand-vma-iterator-interface.patch
mm-mmap-convert-brk-to-use-vma-iterator.patch
kernel-fork-convert-forking-to-using-the-vmi-iterator.patch
mmap-convert-vma_link-vma-iterator.patch
mm-mmap-remove-preallocation-from-do_mas_align_munmap.patch
mmap-change-do_mas_munmap-and-do_mas_aligned_munmap-to-use-vma-iterator.patch
mmap-convert-vma_expand-to-use-vma-iterator.patch
mm-add-temporary-vma-iterator-versions-of-vma_merge-split_vma-and-__split_vma.patch
ipc-shm-use-the-vma-iterator-for-munmap-calls.patch
userfaultfd-use-vma-iterator.patch
mm-change-mprotect_fixup-to-vma-iterator.patch
mlock-convert-mlock-to-vma-iterator.patch
coredump-convert-to-vma-iterator.patch
mempolicy-convert-to-vma-iterator.patch
task_mmu-convert-to-vma-iterator.patch
sched-convert-to-vma-iterator.patch
madvise-use-vmi-iterator-for-__split_vma-and-vma_merge.patch
mmap-pass-through-vmi-iterator-to-__split_vma.patch
mmap-use-vmi-version-of-vma_merge.patch
mm-mremap-use-vmi-version-of-vma_merge.patch
mm-switch-vma_merge-split_vma-and-__split_vma-to-vma-iterator.patch
mmap-convert-__vma_adjust-to-use-vma-iterator.patch
mm-pass-through-vma-iterator-to-__vma_adjust.patch
madvise-use-split_vma-instead-of-__split_vma.patch
mm-remove-unnecessary-write-to-vma-iterator-in-__vma_adjust.patch
mm-pass-vma-iterator-through-to-__vma_adjust.patch
mm-add-vma-iterator-to-vma_adjust-arguments.patch
mmap-clean-up-mmap_region-unrolling.patch
mm-change-munmap-splitting-order-and-move_vma.patch
mm-mmap-move-anon_vma-setting-in-__vma_adjust.patch
mm-mmap-refactor-locking-out-of-__vma_adjust.patch
mm-mmap-use-vma_prepare-and-vma_complete-in-vma_expand.patch
mm-mmap-introduce-init_vma_prep-and-init_multi_vma_prep.patch
mm-dont-use-__vma_adjust-in-__split_vma.patch
mm-mmap-dont-use-__vma_adjust-in-shift_arg_pages.patch
mm-mmap-introduce-dup_vma_anon-helper.patch
mm-mmap-convert-do_brk_flags-to-use-vma_prepare-and-vma_complete.patch
mm-mmap-remove-__vma_adjust.patch
vma_merge-set-vma-iterator-to-correct-position.patch
